Association between Tp-e/QT ratio and prognosis in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

Abstract

Background: Both the Tpeak-Tend interval (Tp-e) and the Tp-e/QT ratio have been linked to increased risk for arrhythmia. Patient Tp-e/QT ratios were investigated prior to primary percutaneous coronary intervention (pPCI) in patients with ST-segment elevation myocardial infarction (STEMI). Hypothesis: Tp-e/QT ratio maybe asscioated with the prognosis in patients with ST-segment elevation. Methods: A total of 338 patients (N = 338) with STEMI treated by pPCI were included. The Tp-e and Tp-e/QT ratio were determined using electrocardiograms in the subjects exhibiting ST-segment elevation. Results: The Tp-e/QT ratio was correlated with both short- and long-term outcomes. Analysis of the receiver operating characteristic curve demonstrated that the optimal cutoff value for outcome prediction was a Tp-e/QT ratio of 0.29. Of the 388 patients enrolled, 115 (34.0%) exhibited a Tp-e/QT ratio ≥0.29. Patients with a Tp-e/QT ratio ≥0.29 showed elevated rates of both in-hospital death (21.9% vs 2.3%; P < 0.001) and main adverse cardiac events (MACE) (48.1% vs 15.3%; P < 0.005). After discharge, Tp-e/QT ratios ≥0.29 remained an independent predictor of all-cause death (35.5% vs 5.2%, P < 0.001) and cardiac death (32.3% vs 2.6%, P < 0.001). Conclusions: The Tp-e/QT ratio may serve as a prognostic predictor of adverse outcomes after successful pPCI treatment in STEMI patients. © 2012 Wiley Periodicals, Inc.